There are a few ways you can help out.
Published material certainly has typos and awkward sentences. Somethings may be unclear. If you find errors or have suggestions, you can contact me via email, chat, or by opening a GitLab issue.
If you're a doctor, paramedic, nurse, or other highly qualified medical provider, you can always review things against modern best practices. I know I'm not an expert and am more than willing to make changes.
At the time it was published, the wish list of illustrations was incomplete. If you want to add illustrations for the next revision, get in touch.
There has been interest in translating Riot Medicine into other languages. I can help others connect on this, and I may be able to help with some of the coordiation, but I do not have the bandwidth to be a central figure in such efforts. Doing so will likely need to be self-organized.